1. Field of Invention
The present invention relates to a semiconductor device provided with a storage element.
2. Description of the Related Art
In recent years, development has been advanced on a semiconductor device having various functions in which a plurality of circuits are integrated over an insulating surface. Further, development has been advanced on a semiconductor device which can send and receive data wirelessly by providing an antenna. Such a semiconductor device is referred to as a wireless chip (also referred to as an ID tag, an IC tag, an IC chip, an RF (Radio Frequency) tag, a wireless tag, an electronic tag, or an RFID (Radio Frequency Identification) tag), and has already been introduced into some markets
Many of semiconductor devices that are currently in practical use have circuits using semiconductor substrates such as Si (the circuits are also referred to as ICs (Integrated Circuits)) and antennas, and the IC chip includes a storage circuit (also called a memory), a controlling circuit, and the like. In particular, a more sophisticated and higher-value-added semiconductor device can be provided when a storage circuit capable of storing a large amount of data is provided. Moreover, it has been required to manufacture these semiconductor devices at low cost, and in recent years, development has been conducted extensively on an organic memory, an organic TFT, and the like which use an organic compound in a controlling circuit, a storage circuit, and the like (for example, see Reference 1: Japanese Patent Application Laid-Open No. 2004-47791).
The storage circuit is, for example, a DRAM (Dynamic Random Access Memory), an SRAM (Static Random Access Memory), an FeRAM (Ferroelectric Random Access Memory), a mask ROM (Read Only Memory), an EPROM (Electrically Programmable Read Only Memory), an EEPROM (Electrically Erasable and Programmable Read Only Memory), a flash memory, or the like. Among these, since a DRAM and an SRAM are volatile storage circuits in which data are erased by turning off the power, data need to be written every time the power is turned on. Meanwhile, an FeRAM is a nonvolatile storage circuit. However, since an FeRAM uses a capacitor element including a ferroelectric layer, the number of manufacturing steps increases. Although a mask ROM has a simple structure, data need to be written in the manufacturing step and data cannot be additionally recorded. An EPROM, an EEPROM, and a flash memory are nonvolatile storage circuits; however, the number of manufacturing steps increases because an element including two gate electrodes is used.